Understanding Your Ergonomic Chair Adjustments
Not all chairs are created equally. For a chair to be considered ergonomic it has to have more than a few ergonomic adjustments. Is your chair truly an ergonomic adjustable chair? The following list explains why chair adjustments are so important to workstation ergonomics.
1. SEAT HEIGHT
Users should be able to sit with their feet comfortably on the floor or footrest without undue pressure on the underside of the thighs. The thigh-to-torso angle should not be less than 90’.
2. SEAT DEPTH
Users should be able to sit in the chair without undue pressure against the back of the knees, with their back properly supported by the backrest and with adequate buttock and thigh support.
3. SEAT WIDTH
The seat should be wider than the hip breadth of the user with allowance for movement and clothing. The seat width should not limit the ability to use the armrests comfortably.
4. SEAT PAN ANGLE
This should allow users to support their feet on the floor or footrest. They should not cause the user’s torso-to-thigh angle to be less than 90’. Forward seat pan angles should not cause users to shift excessive weight to their feet or experience the sensation of sliding out of the chair.
5. BACK SUPPORT
SEAT BACKREST HEIGHT. All backrests should provide adequate lumbar support and buttocks clearance. For tasks requiring upper body mobility, the backrest should not interfere with the user’s movement. For users who prefer reclining postures or greater upper back support, the back height should provide support for the shoulder blades.
BACKREST WIDTH. The width of the backrest should provide adequate support for the curvature of the user’s back without causing localized pressure points.
LUMBAR SUPPORT. The height and shape of the lumbar support should coincide with the lumbar curve (’the small’) of the user’s back. The support should be firm, but not cause localized pressure points.
6. MOVEMENTS OF THE SEAT PAN AND BACK SUPPORT
The user should be able to sit in a position where the torso-to-thigh angle is equal to or greater than 90’. The seat and backrest angles should accommodate the varying postures assumed by the user throughout the day.
7. ARM SUPPORT
ARMREST HEIGHT. This should allow users to sit in a variety of postures while supporting their forearms and/or elbows in a manner that avoids lifting the shoulders (armrests too high) or leaning to the side to reach the armrest (armrests too low). The armrest height should allow accessibility to, and performance of, tasks.
ARMREST LENGTH. The length of the armrest should allow users to sit close enough to the work surface to perform their tasks while maintaining contact with the backrest
INSIDE DISTANCE BETWEEN ARMRESTS. Armrests should allow users to sit in a variety of postures while supporting their forearms in a manner that avoids lifting the shoulders and/or excessive outward positioning of the elbows. Armrests should allow accessibility to, and performance of, tasks. The inside distance between the armrests should allow the user to enter and exit the chair easily. The hips should comfortably fit between the armrests or supports.
If your workstation needs updating, call The Office People today at 843-769.7774.
